水泥膨润土泥浆固结体渗透性与微观结构的关系

Relationship Between Permeability and Microstructure of Cement Bentonite Slurry Concretion

摘要:

采用压汞试验测定了水泥膨润土泥浆固结体的孔隙结构特征,通过室内渗透试验测定了固结体的渗透系数.在试验结果基础上,分析了水泥、膨润土用量及固结体微观孔隙特征参数与其渗透性之间的联系.研究结果表明:水泥膨润土泥浆固结体的渗透性主要受其临界孔径的控制,临界孔径越小,抗渗性越好.其余孔隙结构特征参数与固结体的渗透特性关系不大.随着水泥、膨润土用量的增加,固结体的临界孔径会逐步减少,并且,水泥用量对临界孔径的影响比膨润土更显著.

关键词:水泥膨润土泥浆固结体; 微观结构; 临界孔径; 渗透系数; 压汞试验

Abstract:

The structure of pores in the concretion of cement bentonite slurry is measured by mercuryinjection method,and the permeability coefficient of the concretion is measured by permeability test.According to the test results,the connections between the permeability and pore structure as well as the dosage of cenment and bentonite in the cement bentonite slurry are analyzed.The analysis reveals that the permeability of cementbentonite slurry concretion is controlled mainly by critical size of pores in the concretion.The smaller the critical size of pores,the stronger the permeability resistance of the concretion is,and other pore structure parameters have little influence on the permeability of the concretion.With the increase of the dosage of cement and bentonite,the critical pore size of the concretion will gradually decrease,and the dosage of cement has greater influence on the critical size of pores than that of bentonite.

Key words:cementbentonite slurry concretion; microstructure; critical size of pores; permeability coefficient; mercuryinjection method